JP2762178B2 - Card-type electronic tuner for TV reception - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic tuner, and more particularly to an improvement in the form of such an electronic tuner.

[0002]

2. Description of the Related Art A television receiver requires a tuner, and as such a tuner, an electronic tuner has recently been widely used. An electronic tuner is often provided with a tuner circuit section and a channel control circuit section for selectively tuning both UHF and VHF signals.

[0003] Such an electronic tuner is built in the main body of a television receiver.

[0004]

At present, in addition to the above-mentioned television receivers, for example, a personal computer having a display, such as a so-called 8-mm video device, is commonly used as a device having a video display function. And information equipment. As a matter of course,
Since these video and information devices do not have a built-in tuner, they cannot receive television broadcasts and output their video and audio.

[0005] However, these video and information devices often already have sufficient functions to be used as a television receiver if they have a tuner. Therefore, if these video equipment or information equipment can be used as a television receiver if necessary, the use of these equipment can be expanded, and as a result, the commercial value can be increased. it can.

Accordingly, the present invention seeks to satisfy the above-mentioned needs by improving the structure of the electronic tuner.

[0007]

According to the present invention, there is provided a card-type electronic tuner for TV reception in order to solve the above technical problems.

[0008] The card-type electronic tuner for TV reception is composed of:
A stepped card-shaped case having a thin portion and a thick portion,
A circuit board that constitutes a tuner circuit section, a channel control circuit section, and a demodulation circuit section housed in a thick section of the case; and is electrically connected to the circuit board and arranged along one end face of the thin section of the case. And a connector to be used.

[0009]

According to the present invention, circuits necessary for an electronic tuner, including peripheral circuits necessary for reception, are housed in a card type case, and all input / output of signals is performed via a connector. it can.

[0010]

Therefore, according to the present invention, a card-type electronic tuner such as an IC memory card can be obtained. Such a card-type electronic tuner is easy to store and carry, and is suitable for handling as an optional accessory for various video or information devices. For this reason, it is not necessary to store functions that are not always used, such as a function as a television receiver in a video device or an information device, in the main body of these devices, so that the size and weight of such devices are increased. Can be prevented.

Further, the card-type electronic tuner for TV reception according to the present invention includes all necessary circuits for the tuner including peripheral circuits required for reception, and all input and output of signals are performed via connectors. Since they can be performed, they can be made to function as a television receiver when necessary, for example, by attaching them to the main body of a video device or information device. In this case, the card-type electronic tuner for TV reception can be mounted on the main body of the video device or the information device. For example, a slot may be provided, and a connector paired with a connector provided in the TV-type card-type electronic tuner may be provided in connection with the slot. If such a slot can be shared with another function card, it becomes easy to provide a plurality of optional functions to one device by, for example, switching with a switch. In addition, the card-type electronic tuner for TV reception handles high-frequency signals, and therefore is susceptible to electromagnetic influences between components in the inside thereof. In particular, the cover approaches directly above the circuit member, and the mutual influence is remarkable. By making the portion for housing the circuit portion a thick portion, the separation distance between the cover and the circuit portion can be increased. In addition, since the case is stepped, the direction can be easily determined, which is convenient at the time of mounting. Furthermore, the provision of the connector on the end surface of the thin portion of the case minimizes the cross-sectional area. Therefore, the opening area and the occupied volume of the inside of the set main body in which the case is mounted can be reduced, and downsizing of the main body can be realized.

[0012]

FIG. 1 is a perspective view showing an external appearance of a card-type electronic tuner 1 according to an embodiment of the present invention. FIG.
FIG. 2 is an enlarged sectional view taken along line II-II in FIG. 1. FIG.
FIG. 2 is a block diagram showing an electric circuit provided in the card-type electronic tuner 1.

The card type electronic tuner 1 has a card type case 2. Case 2 is frame 3, frame 3
An upper cover 4 for closing the upper opening of the frame 3 and a lower cover 5 for closing the lower opening of the frame 3 are provided. Such a case 2 is preferably made substantially the same size as a commonly used IC memory card.

The frame 3 is formed of a molded product made of a synthetic resin having increased rigidity, such as polyphenylene sulfide, polyethylene terephthalate, or polycarbonate reinforced with glass fibers. Such a frame 3 may be provided with metal plating, conductive coating, or the like on necessary portions for the purpose of improving the shielding properties. The frame 3 may be made of a material such as an aluminum alloy in addition to the synthetic resin described above.

The upper cover 4 and the lower cover 5 are made of a conductive material such as a metal plate in order to exhibit a shielding property.

In such a case 2, a circuit board is housed. The circuit board comprises a printed circuit board 6 in this embodiment. On the printed circuit board 6, for example,
A double-sided wiring type made of a glass epoxy substrate having a thickness of 0.5 mm is used. On the upper surface of the printed circuit board 6, required electronic components 7 and connectors 8 are surface-mounted. On the lower surface of the printed circuit board 6, required wiring and ground wiring are provided, which are electrically connected to the wiring on the upper surface via through holes. Although not shown, the lower surface of the printed circuit board 6 is covered with an insulating film.

The printed circuit board 6 may be made of a ceramic material, for example, or may have a multilayer structure. When the ground pattern can be formed on most of the lower surface of the printed circuit board, the above-described lower cover 5 can be omitted.
However, it is preferable to provide the lower cover 5 for aesthetics and rigidity. The outer surfaces of the lower cover 5 and the upper cover 4 can be appropriately used as surfaces for printing or the like.

As described above, the connector 8 surface-mounted on the printed circuit board 6 is of a socket type, and is arranged, for example, along the short side of the case 2.

The printed circuit board 6 on which required electronic components 7 and connectors 8 are mounted is positioned mainly in the case 2 by the frame 3. The upper cover 4 and the lower cover 5 are fixed to the frame 3 by, for example, screwing, bonding, welding, or the like.

Various circuits are formed on the printed circuit board 6 as represented by the electronic components 7 shown in FIG. A circuit formed on the printed circuit board 6 is shown in FIG.

Referring to FIG. 3, circuits formed on printed circuit board 6 are roughly divided into a tuner circuit section 9, a channel control circuit section 10, and a demodulation circuit section 11.
Further, the tuner circuit section 9 includes a VHF circuit section 12 and a UHF circuit section.
An HF circuit unit 13 is provided.

U input from U / V signal input terminal 14
The HF / VHF signal is distributed by the distributor 15 and input to the corresponding circuit unit 12 or 13. These circuit units 12 and 13 are respectively provided with bandpass filters 16
And 17, amplifiers 18 and 19, and bandpass filters 20 and 21.

The channel control circuit section 10 includes a channel control circuit 22, and the output of the channel control circuit 22 is input to local oscillation circuits 23 and 24. The local oscillation signal output from one local oscillation circuit 24 is mixed with the high-frequency signal output from the band-pass filter 21 of the UHF circuit unit 13 in the mixing circuit 25, and then amplified in the mixing / amplification circuit 26. You. On the other hand,
The local oscillation signal output from the local oscillation circuit 23 is mixed in the mixing / amplification circuit 26 with the high-frequency signal output from the bandpass filter 20 of the VHF circuit unit 12.

The intermediate frequency signal output from the mixing / amplifying circuit 26 is input to an amplifier 28 provided in the demodulation circuit section 11 through a band pass filter 27. The signal amplified by the amplifier 28 is input to the demodulation circuit 30 via the surface acoustic wave filter 29. In the demodulation circuit 30, the video signal is subjected to AM detection and the audio signal is subjected to FM detection, whereby the video signal and the audio signal are demodulated to be supplied to the video signal output terminal 31 and the audio signal output terminal 32, respectively. Also, from the demodulation circuit 30,
The synchronization signal is supplied to the synchronization signal output terminal 33.

Further, the above-mentioned printed circuit board 6 has a power supply voltage terminal 34 for supplying a power supply voltage to the entire circuit formed thereon, and a channel control circuit section 10.
A tuning voltage terminal 35 for supplying a tuning voltage to the
A clock terminal 36 for supplying a data signal and an enable signal, a data terminal 37 and an enable terminal 35, and a ground terminal 39 are formed.

The terminals 14, 31 to 39 thus formed on the printed circuit board 6 are electrically connected to corresponding contacts provided on the connector 8, respectively.

The above-described tuner circuit section 9, channel control circuit section 10 and demodulation circuit section 11 are respectively shown in FIG.
, The first area 40 and the second area 4 partitioned by broken lines
The first and third regions 42 are arranged. First area 40
VHF circuit section 12 included in tuner circuit section 9 in FIG.
And the positional relationship between the UHF circuit unit 13 can be arbitrarily changed. In the case 2, a shield plate (not shown) that divides the tuner circuit section 9, the channel control circuit section 10, and the demodulation circuit section 11 from each other is arranged. Such a shield plate is preferably brought into electrical contact with the upper cover 4 and the lower cover 5, and the ground wiring of the printed circuit board 6, so that the overall shielding performance is ensured.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an external appearance of a card-type electronic tuner 1 according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view taken along line II-II in FIG.

FIG. 3 is a block diagram showing an electric circuit formed on the printed circuit board 6 shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Card-type electronic tuner 2 Case 6 Printed circuit board 7 Electronic component 8 Connector 9 Tuner circuit part 10 Channel control circuit part 11 Demodulation circuit part 12 VHF circuit part 13 UHF circuit part

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Haruichi Arai 2-26-10 Tenjin, Nagaokakyo-shi, Kyoto Inside Murata Manufacturing Co., Ltd. (72) Yoji Maeda 2-26-10 Tenjin, Nagaokakyo-shi, Kyoto Inside Murata Manufacturing Co., Ltd. (72) Inventor Katsuo Ito 2-26-10 Tenjin, Nagaokakyo-shi, Kyoto Prefecture Inside Murata Manufacturing Co., Ltd. (72) Kazunori Kinoshita 2-26-10 Tenjin, Nagaokakyo-shi, Kyoto Stock Company (56) References JP-A-60-52177 (JP, A) JP-A-63-114519 (JP, U) Tokiohei 2-501650 (JP, A) (58) Fields investigated (Int) .Cl. ⁶ , DB name) H03J 5/24 H03J 5/00 H04B 1/08 H04N 5/64

Claims (1)

(57) [Claims] 1. A stepped card type case having a thin portion and a thick portion, and a circuit board constituting a tuner circuit portion, a channel control circuit portion, and a demodulation circuit portion housed in the thick portion of the case. And a connector electrically connected to the circuit board and arranged along one end surface of the thin portion of the case.